nacos源码-怎么更新配置

界面操作更新nacos配置，然后使用charles抓包工具，抓到请求

http://ip:port/nacos/v1/cs/configs?accessToken=eyJhbGciOiJIUzI1NiJ9.eyJzdWIiOiJuYWNvcyIsImV4cCI6MTYwNTE2Nzc5N30.NNcnIivPaMxj3me9FfKY2VHaWnJNVA6GganyWenR6NU

下载源码

https://github.com/alibaba/nacos

找到请求：nacos/v1/cs/configs

在Constants.java类中找到

public static final String BASE_PATH = "/v1/cs";
    
public static final String CONFIG_CONTROLLER_PATH = BASE_PATH + "/configs";

找到使用CONFIG_CONTROLLER_PATH的controller请求

/**
 * Special controller for soft load client to publish data.
 *
 * @author leiwen
 */
@RestController
@RequestMapping(Constants.CONFIG_CONTROLLER_PATH)
public class ConfigController {

根据请求地址以及参数，定位到请求的方法为publishConfig

/**
 * Adds or updates non-aggregated data.
 *
 * @throws NacosException NacosException.
 */
@PostMapping
@Secured(action = ActionTypes.WRITE, parser = ConfigResourceParser.class)
public Boolean publishConfig(HttpServletRequest request, HttpServletResponse response,
        @RequestParam(value = "dataId") String dataId, @RequestParam(value = "group") String group,
        @RequestParam(value = "tenant", required = false, defaultValue = StringUtils.EMPTY) String tenant,
        @RequestParam(value = "content") String content, @RequestParam(value = "tag", required = false) String tag,
        @RequestParam(value = "appName", required = false) String appName,
        @RequestParam(value = "src_user", required = false) String srcUser,
        @RequestParam(value = "config_tags", required = false) String configTags,
        @RequestParam(value = "desc", required = false) String desc,
        @RequestParam(value = "use", required = false) String use,
        @RequestParam(value = "effect", required = false) String effect,
        @RequestParam(value = "type", required = false) String type,
        @RequestParam(value = "schema", required = false) String schema) throws NacosException {
    
    final String srcIp = RequestUtil.getRemoteIp(request);
    final String requestIpApp = RequestUtil.getAppName(request);
    srcUser = RequestUtil.getSrcUserName(request);
    //check type
    if (!ConfigType.isValidType(type)) {
        type = ConfigType.getDefaultType().getType();
    }
    // check tenant
    // 校验参数的代码
    
    if (AggrWhitelist.isAggrDataId(dataId)) {
        LOGGER.warn("[aggr-conflict] {} attemp to publish single data, {}, {}", RequestUtil.getRemoteIp(request),
                dataId, group);
        throw new NacosException(NacosException.NO_RIGHT, "dataId:" + dataId + " is aggr");
    }
    
    final Timestamp time = TimeUtils.getCurrentTime();
    String betaIps = request.getHeader("betaIps");
    ConfigInfo configInfo = new ConfigInfo(dataId, group, tenant, appName, content);
    configInfo.setType(type);
    if (StringUtils.isBlank(betaIps)) {
        if (StringUtils.isBlank(tag)) {
            persistService.insertOrUpdate(srcIp, srcUser, configInfo, time, configAdvanceInfo, true);
            ConfigChangePublisher
                    .notifyConfigChange(new ConfigDataChangeEvent(false, dataId, group, tenant, time.getTime()));
        } else {
            persistService.insertOrUpdateTag(configInfo, tag, srcIp, srcUser, time, true);
            ConfigChangePublisher.notifyConfigChange(
                    new ConfigDataChangeEvent(false, dataId, group, tenant, tag, time.getTime()));
        }
    } else {
        // beta publish
        persistService.insertOrUpdateBeta(configInfo, betaIps, srcIp, srcUser, time, true);
        ConfigChangePublisher
                .notifyConfigChange(new ConfigDataChangeEvent(true, dataId, group, tenant, time.getTime()));
    }
    ConfigTraceService
            .logPersistenceEvent(dataId, group, tenant, requestIpApp, time.getTime(), InetUtils.getSelfIP(),
                    ConfigTraceService.PERSISTENCE_EVENT_PUB, content);
    return true;
}

逻辑并不复杂，就是判断是新增配置还是修改配置，然后修改或者新增数据库响应信息。

之后通过消息队列通知其他服务，其他服务接收到通知之后，更新配置。

2 源码值得学习的地方

2.1 构造器注入service

不建议直接使用@Autowired注入，建议使用构造器注入或者getter/setter方法注入。

private final ConfigServletInner inner;

private final PersistService persistService;

private final ConfigSubService configSubService;

@Autowired
public ConfigController(ConfigServletInner configServletInner, PersistService persistService,
        ConfigSubService configSubService) {
    this.inner = configServletInner;
    this.persistService = persistService;
    this.configSubService = configSubService;
}

2.2 判断对向是否为空

可以使用 rt.jar 中的Objects对象的 isNull() 方法。

    @Override
    public void insertOrUpdate(String srcIp, String srcUser, ConfigInfo configInfo, Timestamp time,
            Map<String, Object> configAdvanceInfo, boolean notify) {
        if (Objects.isNull(findConfigInfo(configInfo.getDataId(), configInfo.getGroup(), configInfo.getTenant()))) {
            addConfigInfo(srcIp, srcUser, configInfo, time, configAdvanceInfo, notify);
        } else {
            updateConfigInfo(configInfo, srcIp, srcUser, time, configAdvanceInfo, notify);
        }
    }

2.3 插入数据，主键使用雪花算法生成

 private void addConfigInfo(final String srcIp, final String srcUser, final ConfigInfo configInfo,
            final Timestamp time, final Map<String, Object> configAdvanceInfo, final boolean notify,
            BiConsumer<Boolean, Throwable> consumer) {
        
        try {
            final String tenantTmp =
                    StringUtils.isBlank(configInfo.getTenant()) ? StringUtils.EMPTY : configInfo.getTenant();
            configInfo.setTenant(tenantTmp);
            
            long configId = idGeneratorManager.nextId(RESOURCE_CONFIG_INFO_ID);
            long hisId = idGeneratorManager.nextId(RESOURCE_CONFIG_HISTORY_ID);
            
            addConfigInfoAtomic(configId, srcIp, srcUser, configInfo, time, configAdvanceInfo);
            String configTags = configAdvanceInfo == null ? null : (String) configAdvanceInfo.get("config_tags");
            
            addConfigTagsRelation(configId, configTags, configInfo.getDataId(), configInfo.getGroup(),
                    configInfo.getTenant());
            insertConfigHistoryAtomic(hisId, configInfo, srcIp, srcUser, time, "I");
            EmbeddedStorageContextUtils.onModifyConfigInfo(configInfo, srcIp, time);
            databaseOperate.blockUpdate(consumer);
        } finally {
            EmbeddedStorageContextUtils.cleanAllContext();
        }
    }

雪花算法实现类SnowFlowerIdGenerator.java